This invention relates to the decolorization and dewatering of polyether polyols.
Polyether polyols are well known raw materials for the preparation of polyurethanes. One problem associated with commercially available polyether polyols is that they tend to be somewhat yellow in color. For most applications, this is not a significant drawback, but in a growing number of applications, the cosmetic attributes of the polyurethane are a significant factor. For these applications, it is desired that the polyurethane be as colorless (white) as possible. Accordingly, it is necessary that the polyether polyol used in making the polyurethane be water-white if possible.
Various antioxidant and preservatives have been used in attempts to reduce the yellow color of the polyether polyols. However, these have the drawbacks of inadequate performance and being relatively expensive. In addition, the polyol, and therefore the polyurethane made therefrom, will contain residual quantities of these antioxidants and preservatives, which in certain circumstances could leach out, contaminating its surroundings.
Accordingly, an improved process by which a polyether polyol can be decolorized would be highly desirable.